No error if account has no bookings

[luxflux]

This prevents NoMethodError in Accounts#show: undefined method 'value_date' for nil:NilClass.

[stevschmid]

👍

[huerlisi]

Wow, that's old code:-) Remember the days when we had to use h to escape everything;-)

I'll merge this as it fixes the issue. This part of code needs some love though to get it up to date and fix the probably related issue in Bookyt: huerlisi/bookyt#71

I'll do a release today or tomorrow. Thanks for the fix!

[huerlisi]

I'm working on some more cleanup in this area. Especially to also fix huerlisi/bookyt#71

I try to understand how this issue could show up in the first place. It looks like the only place where we use these partials is in https://github.com/huerlisi/has_accounts_engine/blob/master/app/views/accounts/_show_bookings.html.haml#L17 where we already check for an empty @bookings var.

Could you point me to the instances the issue showed up, so I can ensure I won't re-introduce it.

[luxflux]

Well, we had the error after we created a new tenant and loaded the de-CH seeds in Bookyt.
There is a default account plan created where all of the accounts raised this error.